<?php

if (!defined('BASEPATH'))
	exit('No direct script access allowed');
/**
 * CodeIgniter
 *
 * An open source application development framework for PHP 5.1.6 or newer
 *
 * @package		CodeIgniter
 * @author		ExpressionEngine Dev Team
 * @copyright	Copyright (c) 2008 - 2011, EllisLab, Inc.
 * @license		http://codeigniter.com/user_guide/license.html
 * @link		http://codeigniter.com
 * @since		Version 1.0
 * @filesource
 */
// ------------------------------------------------------------------------

/**
 * Loader Class
 *
 * Loads views and files
 *
 * @package		CodeIgniter
 * @subpackage	Libraries
 * @author		ExpressionEngine Dev Team
 * @category	Loader
 * @link		http://codeigniter.com/user_guide/libraries/loader.html
 */
class CI_Loader {

	// All these are set automatically. Don't mess with them.
	/**
	 * Nesting level of the output buffering mechanism
	 *
	 * @var int
	 * @access protected
	 */
	protected $_ci_ob_level;

	/**
	 * List of paths to load views from
	 *
	 * @var array
	 * @access protected
	 */
	protected $_ci_view_paths = array();

	/**
	 * List of paths to load libraries from
	 *
	 * @var array
	 * @access protected
	 */
	protected $_ci_library_paths = array();

	/**
	 * List of paths to load models from
	 *
	 * @var array
	 * @access protected
	 */
	protected $_ci_model_paths = array();

	/**
	 * List of paths to load helpers from
	 *
	 * @var array
	 * @access protected
	 */
	protected $_ci_helper_paths = array();
	protected $_ci_util_paths = array();

	/**
	 * List of loaded base classes
	 * Set by the controller class
	 *
	 * @var array
	 * @access protected
	 */
	protected $_base_classes = array(); // Set by the controller class
	/**
	 * List of cached variables
	 *
	 * @var array
	 * @access protected
	 */
	protected $_ci_cached_vars = array();

	/**
	 * List of loaded classes
	 *
	 * @var array
	 * @access protected
	 */
	protected $_ci_classes = array();

	/**
	 * List of loaded files
	 *
	 * @var array
	 * @access protected
	 */
	protected $_ci_loaded_files = array();

	/**
	 * List of loaded models
	 *
	 * @var array
	 * @access protected
	 */
	protected $_ci_models = array();
	protected $_ci_utils = array();

	/**
	 * List of loaded helpers
	 *
	 * @var array
	 * @access protected
	 */
	protected $_ci_helpers = array();

	/**
	 * List of class name mappings
	 *
	 * @var array
	 * @access protected
	 */
	protected $_ci_varmap = array('unit_test' => 'unit',
	    'user_agent' => 'agent');

	/**
	 * Constructor
	 *
	 * Sets the path to the view files and gets the initial output buffering level
	 */
	public function __construct() {
		$this->_ci_ob_level = ob_get_level();
		$this->_ci_library_paths = array(APPPATH, BASEPATH);
		$this->_ci_helper_paths = array(APPPATH, BASEPATH);
		$this->_ci_util_paths = array(APPPATH, BASEPATH);
		$this->_ci_model_paths = array(APPPATH);
		$this->_ci_view_paths = array(APPPATH . 'views/' => TRUE);

		log_message('debug', "Loader Class Initialized");
	}

	// --------------------------------------------------------------------

	/**
	 * Initialize the Loader
	 *
	 * This method is called once in CI_Controller.
	 *
	 * @param 	array
	 * @return 	object
	 */
	public function initialize() {
		$this->_ci_classes = array();
		$this->_ci_loaded_files = array();
		$this->_ci_models = array();
		$this->_ci_utils = array();
		$this->_base_classes = & is_loaded();

		$this->_ci_autoloader();

		return $this;
	}

	// --------------------------------------------------------------------

	/**
	 * Is Loaded
	 *
	 * A utility function to test if a class is in the self::$_ci_classes array.
	 * This function returns the object name if the class tested for is loaded,
	 * and returns FALSE if it isn't.
	 *
	 * It is mainly used in the form_helper -> _get_validation_object()
	 *
	 * @param 	string	class being checked for
	 * @return 	mixed	class object name on the CI SuperObject or FALSE
	 */
	public function is_loaded($class) {
		if (isset($this->_ci_classes[$class])) {
			return $this->_ci_classes[$class];
		}

		return FALSE;
	}

	// --------------------------------------------------------------------

	/**
	 * Class Loader
	 *
	 * This function lets users load and instantiate classes.
	 * It is designed to be called from a user's app controllers.
	 *
	 * @param	string	the name of the class
	 * @param	mixed	the optional parameters
	 * @param	string	an optional object name
	 * @return	void
	 */
	public function library($library = '', $params = NULL, $object_name = NULL) {
		if (is_array($library)) {
			foreach ($library as $class) {
				$this->library($class, $params);
			}

			return;
		}

		if ($library == '' OR isset($this->_base_classes[$library])) {
			return FALSE;
		}

		if (!is_null($params) && !is_array($params)) {
			$params = NULL;
		}

		$this->_ci_load_class($library, $params, $object_name);
	}

	// --------------------------------------------------------------------

	/**
	 * Model Loader
	 *
	 * This function lets users load and instantiate models.
	 *
	 * @param	string	the name of the class
	 * @param	string	name for the model
	 * @param	bool	database connection
	 * @return	void
	 */
	public function model($model, $db_config = array(), $name = '', $db_conn = FALSE) {
		if (is_array($model)) {
			foreach ($model as $babe) {
				$this->model($babe);
			}
			return;
		}

		if ($model == '') {
			return;
		}
		//if (!is_array($db_config)) {
		//	return;
		//}
		$path = '';

		// Is the model in a sub-folder? If so, parse out the filename and path.
		if (($last_slash = strrpos($model, '/')) !== FALSE) {
			// The path is in front of the last slash
			$path = substr($model, 0, $last_slash + 1);

			// And the model name behind it
			$model = substr($model, $last_slash + 1);
		}

		if ($name == '') {
			$name = $model;
		}

		if (in_array($name, $this->_ci_models, TRUE)) {
			return;
		}

		$CI = & get_instance();
		if (isset($CI->$name)) {
			show_error('The model name you are loading is the name of a resource that is already being used: ' . $name);
		}

		$model = strtolower($model) . config_item('model_suffix');

		foreach ($this->_ci_model_paths as $mod_path) {
			if (!file_exists($mod_path . 'models/' . $path . $model . '.php')) {
				continue;
			}

			if ($db_conn !== FALSE AND !class_exists('CI_DB')) {

				if ($db_conn === TRUE) {
					$db_conn = '';
				}

				$CI->load->db($db_config, FALSE, TRUE);
			}

			if (!class_exists('CI_Model')) {
				//load_class('Model', 'core');
				require(BASEPATH . 'core/Model.php');
			}

			require_once(BASEPATH . '../' . APPPATH . 'models/' . $path . $model . '.php');
			//$model = ucfirst($model);
			$CI->$name = new $model($db_config);
			$this->_ci_models[] = $name;
			return;
		}

		// couldn't find the model
		show_error('Unable to locate the model you have specified: ' . $model);
	}

	// --------------------------------------------------------------------

	/**
	 * Database Loader
	 *
	 * @param	string	the DB credentials
	 * @param	bool	whether to return the DB object
	 * @param	bool	whether to enable active record (this allows us to override the config setting)
	 * @return	object
	 */
	public function database($params = '', $return = FALSE, $active_record = NULL) {
		// Grab the super object
		$CI = & get_instance();

		// Do we even need to load the database class?
		if (class_exists('CI_DB') AND $return == FALSE AND $active_record == NULL AND isset($CI->db) AND is_object($CI->db)) {
			return FALSE;
		}

		require_once(BASEPATH . 'database/DB.php');

		if ($return === TRUE) {
			return DB($params, $active_record);
		}

		// Initialize the db variable.  Needed to prevent
		// reference errors with some configurations
		$CI->db = '';

		// Load the DB class
		$CI->db = & DB($params, $active_record);
	}

	public function db($params = '', $return = TRUE, $active_record = NULL) {
		$type = isset($params['type']) ? $params['type'] : 'mongo';
		if (!defined('ENVIRONMENT') OR !file_exists($file_path = APPPATH . 'platforms/' . ENVIRONMENT . '/database.php')) {
			if (!file_exists($file_path = APPPATH . 'platforms/database.php')) {
				show_error('The configuration file database.php does not exist.');
			}
		}

		$dbconfig = include $file_path;
		$dbconfig = $dbconfig[$type][$params['dbkey']];
		$dbname = config_item('db_prefix') . ucfirst($type);
		$dbconfig['sec'] = isset($params['sec']) ? $params['sec'] : '';

		require_once(BASEPATH . 'database/' . $dbname . '.php');

		$CI = & get_instance();
		$CI->db = '';
		$CI->db = new $dbname($dbconfig);


		if ($return) {
			$CI->db;
		}
	}

	// --------------------------------------------------------------------

	/**
	 * Load the Utilities Class
	 *
	 * @return	string
	 */
	public function dbutil() {
		if (!class_exists('CI_DB')) {
			$this->database();
		}

		$CI = & get_instance();

		// for backwards compatibility, load dbforge so we can extend dbutils off it
		// this use is deprecated and strongly discouraged
		$CI->load->dbforge();

		require_once(BASEPATH . 'database/DB_utility.php');
		require_once(BASEPATH . 'database/drivers/' . $CI->db->dbdriver . '/' . $CI->db->dbdriver . '_utility.php');
		$class = 'CI_DB_' . $CI->db->dbdriver . '_utility';

		$CI->dbutil = new $class();
	}

	// --------------------------------------------------------------------

	/**
	 * Load the Database Forge Class
	 *
	 * @return	string
	 */
	public function dbforge() {
		if (!class_exists('CI_DB')) {
			$this->database();
		}

		$CI = & get_instance();

		require_once(BASEPATH . 'database/DB_forge.php');
		require_once(BASEPATH . 'database/drivers/' . $CI->db->dbdriver . '/' . $CI->db->dbdriver . '_forge.php');
		$class = 'CI_DB_' . $CI->db->dbdriver . '_forge';

		$CI->dbforge = new $class();
	}

	// --------------------------------------------------------------------

	/**
	 * Load View
	 *
	 * This function is used to load a "view" file.  It has three parameters:
	 *
	 * 1. The name of the "view" file to be included.
	 * 2. An associative array of data to be extracted for use in the view.
	 * 3. TRUE/FALSE - whether to return the data or load it.  In
	 * some cases it's advantageous to be able to return data so that
	 * a developer can process it in some way.
	 *
	 * @param	string
	 * @param	array
	 * @param	bool
	 * @return	void
	 */
	public function view($view, $vars = array(), $return = FALSE) {
		return $this->_ci_load(array('_ci_view' => $view, '_ci_vars' => $this->_ci_object_to_array($vars), '_ci_return' => $return));
	}

	public function json($vars = array()) {
		ob_start();
		echo json_encode($vars, TRUE);
		//$buffer = ob_get_contents();
		$buffer = ob_get_flush();
		//@ob_end_clean();
		return $buffer;
	}

	// --------------------------------------------------------------------

	/**
	 * Load File
	 *
	 * This is a generic file loader
	 *
	 * @param	string
	 * @param	bool
	 * @return	string
	 */
	public function file($path, $return = FALSE) {
		return $this->_ci_load(array('_ci_path' => $path, '_ci_return' => $return));
	}

	// --------------------------------------------------------------------

	/**
	 * Set Variables
	 *
	 * Once variables are set they become available within
	 * the controller class and its "view" files.
	 *
	 * @param	array
	 * @param 	string
	 * @return	void
	 */
	public function vars($vars = array(), $val = '') {
		if ($val != '' AND is_string($vars)) {
			$vars = array($vars => $val);
		}

		$vars = $this->_ci_object_to_array($vars);

		if (is_array($vars) AND count($vars) > 0) {
			foreach ($vars as $key => $val) {
				$this->_ci_cached_vars[$key] = $val;
			}
		}
	}

	// --------------------------------------------------------------------

	/**
	 * Get Variable
	 *
	 * Check if a variable is set and retrieve it.
	 *
	 * @param	array
	 * @return	void
	 */
	public function get_var($key) {
		return isset($this->_ci_cached_vars[$key]) ? $this->_ci_cached_vars[$key] : NULL;
	}

	// --------------------------------------------------------------------

	/**
	 * Load Helper
	 *
	 * This function loads the specified helper file.
	 *
	 * @param	mixed
	 * @return	void
	 */
	public function helper($helpers = array()) {
		foreach ($this->_ci_prep_filename($helpers, '_helper') as $helper) {
			if (isset($this->_ci_helpers[$helper])) {
				continue;
			}

			$ext_helper = APPPATH . 'helpers/' . config_item('subclass_prefix') . $helper . '.php';

			// Is this a helper extension request?
			if (file_exists($ext_helper)) {
				$base_helper = BASEPATH . 'helpers/' . $helper . '.php';

				if (!file_exists($base_helper)) {
					show_error('Unable to load the requested file: helpers/' . $helper . '.php');
				}

				include_once($ext_helper);
				include_once($base_helper);

				$this->_ci_helpers[$helper] = TRUE;
				log_message('debug', 'Helper loaded: ' . $helper);
				continue;
			}

			// Try to load the helper
			foreach ($this->_ci_helper_paths as $path) {
				if (file_exists($path . 'helpers/' . $helper . '.php')) {
					include_once($path . 'helpers/' . $helper . '.php');

					$this->_ci_helpers[$helper] = TRUE;
					log_message('debug', 'Helper loaded: ' . $helper);
					break;
				}
			}

			// unable to load the helper
			if (!isset($this->_ci_helpers[$helper])) {
				show_error('Unable to load the requested file: helpers/' . $helper . '.php');
			}
		}
	}

	// --------------------------------------------------------------------

	/**
	 * Load Helpers
	 *
	 * This is simply an alias to the above function in case the
	 * user has written the plural form of this function.
	 *
	 * @param	array
	 * @return	void
	 */
	public function helpers($helpers = array()) {
		$this->helper($helpers);
	}

	public function util($util, $name = '') {
		if (is_array($util)) {
			foreach ($util as $babe) {
				$this->util($babe);
			}
			return;
		}

		if ($util == '') {
			return;
		}
		//if (!is_array($db_config)) {
		//	return;
		//}
		$path = '';

		// Is the model in a sub-folder? If so, parse out the filename and path.
		if (($last_slash = strrpos($util, '/')) !== FALSE) {
			// The path is in front of the last slash
			$path = substr($util, 0, $last_slash + 1);

			// And the model name behind it
			$model = substr($util, $last_slash + 1);
		}

		if ($name == '') {
			$name = $util;
		}

		if (in_array($name, $this->_ci_utils, TRUE)) {
			return;
		}

		$CI = & get_instance();
		if (isset($CI->$name)) {
			show_error('The util name you are loading is the name of a resource that is already being used: ' . $name);
		}

		$util = strtolower($util) . config_item('util_suffix');

		foreach ($this->_ci_util_paths as $util_path) {
			if (!file_exists($util_path . 'utils/' . $path . $util . '.php')) {
				continue;
			}

			if (!class_exists('CI_Util')) {
				load_class('Util', 'core');
				//require(BASEPATH . 'core/Util.php');
			}

			require_once(BASEPATH . '../' . APPPATH . 'utils/' . $path . $util . '.php');
			//$model = ucfirst($model);
			$CI->$name = new $util();
			$this->_ci_utils[] = $name;
			return;
		}

		// couldn't find the model
		show_error('Unable to locate the model you have specified: ' . $model);
	}

	// --------------------------------------------------------------------

	/**
	 * Loads a language file
	 *
	 * @param	array
	 * @param	string
	 * @return	void
	 */
	public function language($file = array(), $lang = '') {
		$CI = & get_instance();

		if (!is_array($file)) {
			$file = array($file);
		}

		foreach ($file as $langfile) {
			$CI->lang->load($langfile, $lang);
		}
	}

	// --------------------------------------------------------------------

	/**
	 * Loads a config file
	 *
	 * @param	string
	 * @param	bool
	 * @param 	bool
	 * @return	void
	 */
	public function config($file = '', $use_sections = FALSE, $fail_gracefully = FALSE) {
		$CI = & get_instance();
		$CI->config->load($file, $use_sections, $fail_gracefully);
	}

	// --------------------------------------------------------------------

	/**
	 * Driver
	 *
	 * Loads a driver library
	 *
	 * @param	string	the name of the class
	 * @param	mixed	the optional parameters
	 * @param	string	an optional object name
	 * @return	void
	 */
	public function driver($library = '', $params = NULL, $object_name = NULL) {
		if (!class_exists('CI_Driver_Library')) {
			// we aren't instantiating an object here, that'll be done by the Library itself
			require BASEPATH . 'libraries/Driver.php';
		}

		if ($library == '') {
			return FALSE;
		}

		// We can save the loader some time since Drivers will *always* be in a subfolder,
		// and typically identically named to the library
		if (!strpos($library, '/')) {
			$library = ucfirst($library) . '/' . $library;
		}

		return $this->library($library, $params, $object_name);
	}

	// --------------------------------------------------------------------

	/**
	 * Add Package Path
	 *
	 * Prepends a parent path to the library, model, helper, and config path arrays
	 *
	 * @param	string
	 * @param 	boolean
	 * @return	void
	 */
	public function add_package_path($path, $view_cascade = TRUE) {
		$path = rtrim($path, '/') . '/';

		array_unshift($this->_ci_library_paths, $path);
		array_unshift($this->_ci_model_paths, $path);
		array_unshift($this->_ci_helper_paths, $path);
		array_unshift($this->_ci_util_paths, $path);

		$this->_ci_view_paths = array($path . 'views/' => $view_cascade) + $this->_ci_view_paths;

		// Add config file path
		$config = & $this->_ci_get_component('config');
		array_unshift($config->_config_paths, $path);
	}

	// --------------------------------------------------------------------

	/**
	 * Get Package Paths
	 *
	 * Return a list of all package paths, by default it will ignore BASEPATH.
	 *
	 * @param	string
	 * @return	void
	 */
	public function get_package_paths($include_base = FALSE) {
		return $include_base === TRUE ? $this->_ci_library_paths : $this->_ci_model_paths;
	}

	// --------------------------------------------------------------------

	/**
	 * Remove Package Path
	 *
	 * Remove a path from the library, model, and helper path arrays if it exists
	 * If no path is provided, the most recently added path is removed.
	 *
	 * @param	type
	 * @param 	bool
	 * @return	type
	 */
	public function remove_package_path($path = '', $remove_config_path = TRUE) {
		$config = & $this->_ci_get_component('config');

		if ($path == '') {
			$void = array_shift($this->_ci_library_paths);
			$void = array_shift($this->_ci_model_paths);
			$void = array_shift($this->_ci_helper_paths);
			$void = array_shift($this->_ci_util_paths);
			$void = array_shift($this->_ci_view_paths);
			$void = array_shift($config->_config_paths);
		} else {
			$path = rtrim($path, '/') . '/';
			foreach (array('_ci_library_paths', '_ci_model_paths', '_ci_helper_paths', '_ci_util_paths') as $var) {
				if (($key = array_search($path, $this->{$var})) !== FALSE) {
					unset($this->{$var}[$key]);
				}
			}

			if (isset($this->_ci_view_paths[$path . 'views/'])) {
				unset($this->_ci_view_paths[$path . 'views/']);
			}

			if (($key = array_search($path, $config->_config_paths)) !== FALSE) {
				unset($config->_config_paths[$key]);
			}
		}

		// make sure the application default paths are still in the array
		$this->_ci_library_paths = array_unique(array_merge($this->_ci_library_paths, array(APPPATH, BASEPATH)));
		$this->_ci_helper_paths = array_unique(array_merge($this->_ci_helper_paths, array(APPPATH, BASEPATH)));
		$this->_ci_util_paths = array_unique(array_merge($this->_ci_util_paths, array(APPPATH)));
		$this->_ci_model_paths = array_unique(array_merge($this->_ci_model_paths, array(APPPATH)));
		$this->_ci_view_paths = array_merge($this->_ci_view_paths, array(APPPATH . 'views/' => TRUE));
		$config->_config_paths = array_unique(array_merge($config->_config_paths, array(APPPATH)));
	}

	// --------------------------------------------------------------------

	/**
	 * Loader
	 *
	 * This function is used to load views and files.
	 * Variables are prefixed with _ci_ to avoid symbol collision with
	 * variables made available to view files
	 *
	 * @param	array
	 * @return	void
	 */
	protected function _ci_load($_ci_data) {
		// Set the default data variables
		foreach (array('_ci_view', '_ci_vars', '_ci_path', '_ci_return') as $_ci_val) {
			$$_ci_val = (!isset($_ci_data[$_ci_val])) ? FALSE : $_ci_data[$_ci_val];
		}

		$file_exists = FALSE;

		// Set the path to the requested file
		if ($_ci_path != '') {
			$_ci_x = explode('/', $_ci_path);
			$_ci_file = end($_ci_x);
		} else {
			$_ci_ext = pathinfo($_ci_view, PATHINFO_EXTENSION);
			$_ci_file = ($_ci_ext == '') ? $_ci_view . '.php' : $_ci_view;

			foreach ($this->_ci_view_paths as $view_file => $cascade) {
				if (file_exists($view_file . $_ci_file)) {
					$_ci_path = $view_file . $_ci_file;
					$file_exists = TRUE;
					break;
				}

				if (!$cascade) {
					break;
				}
			}
		}

		if (!$file_exists && !file_exists($_ci_path)) {
			show_error('Unable to load the requested file: ' . $_ci_file);
		}

		// This allows anything loaded using $this->load (views, files, etc.)
		// to become accessible from within the Controller and Model functions.

		$_ci_CI = & get_instance();
		foreach (get_object_vars($_ci_CI) as $_ci_key => $_ci_var) {
			if (!isset($this->$_ci_key)) {
				$this->$_ci_key = & $_ci_CI->$_ci_key;
			}
		}

		/*
		 * Extract and cache variables
		 *
		 * You can either set variables using the dedicated $this->load_vars()
		 * function or via the second parameter of this function. We'll merge
		 * the two types and cache them so that views that are embedded within
		 * other views can have access to these variables.
		 */
		if (is_array($_ci_vars)) {
			$this->_ci_cached_vars = array_merge($this->_ci_cached_vars, $_ci_vars);
		}
		extract($this->_ci_cached_vars);

		/*
		 * Buffer the output
		 *
		 * We buffer the output for two reasons:
		 * 1. Speed. You get a significant speed boost.
		 * 2. So that the final rendered template can be
		 * post-processed by the output class.  Why do we
		 * need post processing?  For one thing, in order to
		 * show the elapsed page load time.  Unless we
		 * can intercept the content right before it's sent to
		 * the browser and then stop the timer it won't be accurate.
		 */
		ob_start();
		if ($_ci_return === TRUE) {
			$buffer = ob_get_contents();
			@ob_end_clean();
			return $buffer;
		}
		// If the PHP installation does not support short tags we'll
		// do a little string replacement, changing the short tags
		// to standard PHP echo statements.

		if ((bool) @ini_get('short_open_tag') === FALSE AND config_item('rewrite_short_tags') == TRUE) {
			echo eval('?>' . preg_replace("/;*\s*\?>/", "; ?>", str_replace('<?=', '<?php echo ', file_get_contents($_ci_path))));
		} else {
			include($_ci_path); // include() vs include_once() allows for multiple views with the same name
		}

		log_message('debug', 'File loaded: ' . $_ci_path);

		// Return the file data if requested


		/*
		 * Flush the buffer... or buff the flusher?
		 *
		 * In order to permit views to be nested within
		 * other views, we need to flush the content back out whenever
		 * we are beyond the first level of output buffering so that
		 * it can be seen and included properly by the first included
		 * template and any subsequent ones. Oy!
		 *
		 */
		if (ob_get_level() > $this->_ci_ob_level + 1) {
			ob_end_flush();
		} else {
			$_ci_CI->output->append_output(ob_get_contents());
			@ob_end_clean();
		}
	}

	// --------------------------------------------------------------------

	/**
	 * Load class
	 *
	 * This function loads the requested class.
	 *
	 * @param	string	the item that is being loaded
	 * @param	mixed	any additional parameters
	 * @param	string	an optional object name
	 * @return	void
	 */
	protected function _ci_load_class($class, $params = NULL, $object_name = NULL) {
		// Get the class name, and while we're at it trim any slashes.
		// The directory path can be included as part of the class name,
		// but we don't want a leading slash
		$class = str_replace('.php', '', trim($class, '/'));

		// Was the path included with the class name?
		// We look for a slash to determine this
		$subdir = '';
		if (($last_slash = strrpos($class, '/')) !== FALSE) {
			// Extract the path
			$subdir = substr($class, 0, $last_slash + 1);

			// Get the filename from the path
			$class = substr($class, $last_slash + 1);
		}

		// We'll test for both lowercase and capitalized versions of the file name
		foreach (array(ucfirst($class), strtolower($class)) as $class) {
			$subclass = APPPATH . 'libraries/' . $subdir . config_item('subclass_prefix') . $class . '.php';

			// Is this a class extension request?
			if (file_exists($subclass)) {
				$baseclass = BASEPATH . 'libraries/' . ucfirst($class) . '.php';

				if (!file_exists($baseclass)) {
					log_message('error', "Unable to load the requested class: " . $class);
					show_error("Unable to load the requested class: " . $class);
				}

				// Safety:  Was the class already loaded by a previous call?
				if (in_array($subclass, $this->_ci_loaded_files)) {
					// Before we deem this to be a duplicate request, let's see
					// if a custom object name is being supplied.  If so, we'll
					// return a new instance of the object
					if (!is_null($object_name)) {
						$CI = & get_instance();
						if (!isset($CI->$object_name)) {
							return $this->_ci_init_class($class, config_item('subclass_prefix'), $params, $object_name);
						}
					}

					$is_duplicate = TRUE;
					log_message('debug', $class . " class already loaded. Second attempt ignored.");
					return;
				}

				include_once($baseclass);
				include_once($subclass);
				$this->_ci_loaded_files[] = $subclass;

				return $this->_ci_init_class($class, config_item('subclass_prefix'), $params, $object_name);
			}

			// Lets search for the requested library file and load it.
			$is_duplicate = FALSE;
			foreach ($this->_ci_library_paths as $path) {
				$filepath = $path . 'libraries/' . $subdir . $class . '.php';

				// Does the file exist?  No?  Bummer...
				if (!file_exists($filepath)) {
					continue;
				}

				// Safety:  Was the class already loaded by a previous call?
				if (in_array($filepath, $this->_ci_loaded_files)) {
					// Before we deem this to be a duplicate request, let's see
					// if a custom object name is being supplied.  If so, we'll
					// return a new instance of the object
					if (!is_null($object_name)) {
						$CI = & get_instance();
						if (!isset($CI->$object_name)) {
							return $this->_ci_init_class($class, '', $params, $object_name);
						}
					}

					$is_duplicate = TRUE;
					log_message('debug', $class . " class already loaded. Second attempt ignored.");
					return;
				}

				include_once($filepath);
				$this->_ci_loaded_files[] = $filepath;
				return $this->_ci_init_class($class, '', $params, $object_name);
			}
		} // END FOREACH
		// One last attempt.  Maybe the library is in a subdirectory, but it wasn't specified?
		if ($subdir == '') {
			$path = strtolower($class) . '/' . $class;
			return $this->_ci_load_class($path, $params);
		}

		// If we got this far we were unable to find the requested class.
		// We do not issue errors if the load call failed due to a duplicate request
		if ($is_duplicate == FALSE) {
			log_message('error', "Unable to load the requested class: " . $class);
			show_error("Unable to load the requested class: " . $class);
		}
	}

	// --------------------------------------------------------------------

	/**
	 * Instantiates a class
	 *
	 * @param	string
	 * @param	string
	 * @param	bool
	 * @param	string	an optional object name
	 * @return	null
	 */
	protected function _ci_init_class($class, $prefix = '', $config = FALSE, $object_name = NULL) {
		// Is there an associated config file for this class?  Note: these should always be lowercase
		if ($config === NULL) {
			// Fetch the config paths containing any package paths
			$config_component = $this->_ci_get_component('config');

			if (is_array($config_component->_config_paths)) {
				// Break on the first found file, thus package files
				// are not overridden by default paths
				foreach ($config_component->_config_paths as $path) {
					// We test for both uppercase and lowercase, for servers that
					// are case-sensitive with regard to file names. Check for environment
					// first, global next
					if (defined('ENVIRONMENT') AND file_exists($path . 'config/' . ENVIRONMENT . '/' . strtolower($class) . '.php')) {
						include($path . 'config/' . ENVIRONMENT . '/' . strtolower($class) . '.php');
						break;
					} elseif (defined('ENVIRONMENT') AND file_exists($path . 'config/' . ENVIRONMENT . '/' . ucfirst(strtolower($class)) . '.php')) {
						include($path . 'config/' . ENVIRONMENT . '/' . ucfirst(strtolower($class)) . '.php');
						break;
					} elseif (file_exists($path . 'config/' . strtolower($class) . '.php')) {
						include($path . 'config/' . strtolower($class) . '.php');
						break;
					} elseif (file_exists($path . 'config/' . ucfirst(strtolower($class)) . '.php')) {
						include($path . 'config/' . ucfirst(strtolower($class)) . '.php');
						break;
					}
				}
			}
		}

		if ($prefix == '') {
			if (class_exists('CI_' . $class)) {
				$name = 'CI_' . $class;
			} elseif (class_exists(config_item('subclass_prefix') . $class)) {
				$name = config_item('subclass_prefix') . $class;
			} else {
				$name = $class;
			}
		} else {
			$name = $prefix . $class;
		}

		// Is the class name valid?
		if (!class_exists($name)) {
			log_message('error', "Non-existent class: " . $name);
			show_error("Non-existent class: " . $class);
		}

		// Set the variable name we will assign the class to
		// Was a custom class name supplied?  If so we'll use it
		$class = strtolower($class);

		if (is_null($object_name)) {
			$classvar = (!isset($this->_ci_varmap[$class])) ? $class : $this->_ci_varmap[$class];
		} else {
			$classvar = $object_name;
		}

		// Save the class name and object name
		$this->_ci_classes[$class] = $classvar;

		// Instantiate the class
		$CI = & get_instance();
		if ($config !== NULL) {
			$CI->$classvar = new $name($config);
		} else {
			$CI->$classvar = new $name;
		}
	}

	// --------------------------------------------------------------------

	/**
	 * Autoloader
	 *
	 * The config/autoload.php file contains an array that permits sub-systems,
	 * libraries, and helpers to be loaded automatically.
	 *
	 * @param	array
	 * @return	void
	 */
	private function _ci_autoloader() {
		if (defined('ENVIRONMENT') AND file_exists(APPPATH . 'config/' . ENVIRONMENT . '/autoload.php')) {
			include(APPPATH . 'config/' . ENVIRONMENT . '/autoload.php');
		} else {
			include(APPPATH . 'config/autoload.php');
		}

		if (!isset($autoload)) {
			return FALSE;
		}

		// Autoload packages
		if (isset($autoload['packages'])) {
			foreach ($autoload['packages'] as $package_path) {
				$this->add_package_path($package_path);
			}
		}

		// Load any custom config file
		if (count($autoload['config']) > 0) {
			$CI = & get_instance();
			foreach ($autoload['config'] as $key => $val) {
				$CI->config->load($val);
			}
		}

		// Autoload helpers and languages
		foreach (array('helper', 'language') as $type) {
			if (isset($autoload[$type]) AND count($autoload[$type]) > 0) {
				$this->$type($autoload[$type]);
			}
		}

		// A little tweak to remain backward compatible
		// The $autoload['core'] item was deprecated
		if (!isset($autoload['libraries']) AND isset($autoload['core'])) {
			$autoload['libraries'] = $autoload['core'];
		}

		// Load libraries
		if (isset($autoload['libraries']) AND count($autoload['libraries']) > 0) {
			// Load the database driver.
			if (in_array('database', $autoload['libraries'])) {
				$this->database();
				$autoload['libraries'] = array_diff($autoload['libraries'], array('database'));
			}

			// Load all other libraries
			foreach ($autoload['libraries'] as $item) {
				$this->library($item);
			}
		}

		// Autoload models
		if (isset($autoload['model'])) {
			$this->model($autoload['model']);
		}
	}

	// --------------------------------------------------------------------

	/**
	 * Object to Array
	 *
	 * Takes an object as input and converts the class variables to array key/vals
	 *
	 * @param	object
	 * @return	array
	 */
	protected function _ci_object_to_array($object) {
		return (is_object($object)) ? get_object_vars($object) : $object;
	}

	// --------------------------------------------------------------------

	/**
	 * Get a reference to a specific library or model
	 *
	 * @param 	string
	 * @return	bool
	 */
	protected function &_ci_get_component($component) {
		$CI = & get_instance();
		return $CI->$component;
	}

	// --------------------------------------------------------------------

	/**
	 * Prep filename
	 *
	 * This function preps the name of various items to make loading them more reliable.
	 *
	 * @param	mixed
	 * @param 	string
	 * @return	array
	 */
	protected function _ci_prep_filename($filename, $extension) {
		if (!is_array($filename)) {
			return array(strtolower(str_replace('.php', '', str_replace($extension, '', $filename)) . $extension));
		} else {
			foreach ($filename as $key => $val) {
				$filename[$key] = strtolower(str_replace('.php', '', str_replace($extension, '', $val)) . $extension);
			}

			return $filename;
		}
	}

}

/* End of file Loader.php */
/* Location: ./system/core/Loader.php */